To me, there is nothing more exasperating than having your paint brush run dry before you complete a fine line or surface. This is especially true when painting the bottom of Santa's hat, where one color must butt up against another. It seems that once you have established a good solid paint line, your brush runs dry before you complete the line. When this happens, you must reload the brush to finish. And we all know what happens next - the paint lines don't meet up or the finished paint line runs over onto the other surface.
To help eliminate this, always be sure you start with a fully loaded paint brush; so you can complete the line in one attempt. Each time you must restart the line you run the risk of unmatched painted surfaces.